The present invention was born of a need for a better method of measuring detonation velocity. An explosive chemical reaction is initiated at one point in a mass of explosive material by means such as an electrical potential or ignition of a different explosive used as a detonator. All of the explosive material does not react at the same time; starting at the initiation point, a reaction front moves through the mass of material at a very rapid rate, so rapidly that it appears as if the entire mass of explosive reacted at once. The moving reaction front, or zone in which the reaction is taking place, is commonly called a detonation wave. In testing of explosives, it is necessary to determine the detonation velocity of an explosive, which is the speed at which the detonation wave travels though a mass of the explosive. A detonation wave is electrically conductive. A method of measuring detonation velocity is to place pairs of fine wires at locations within a mass of explosive and note the times at which there is electrical continuity between each pair of wires. The time of arrival of the detonation wave is the time at which electricity will flow from one wire of a pair to another.
Placing pairs of fine copper wires at locations in an explosive in setting up a test is difficult and time consuming. The wires must be of small diameter in order that they do not affect the characteristics which the test is designed to measure. Wires used in testing and experimentation such as the exemplary test described herein have a diameter of 0.002 inch. They tend to tangle and break and shift position. Loss of data points due to problems with detonation wave sensing wires may necessitate repeating an experiment. The present invention solves these problems and provides a sensor with many uses in addition to that which impelled its development.